Pottery Terms Demystified

We thought it might be helpful to define some of the terms we use in our pottery descriptions. First, let's cover the distinctions between the main physical types of pottery: earthenware, stoneware and porcelain.

Earthenware was the first kind of pottery produced, as early as the Upper Paleolithic period. It was probably discovered accidentally when people built fires in clay soil. Typically, earthenware is made with residual or "wild" clays, deposited by nature. It may have all sorts of interesting "grog" in it, such as quartz grains or bits of mica. Earthenware is low-fired pottery, generally heated in pit-fires or bonfires to a temperature between 800 °C (1,470 °F) and 1,200 °C (2,190 °F). The resulting pottery is generally too porous to hold liquids for any length of time; eventually, the development of ceramic glazes solved this problem. Much folk pottery (see below) is earthenware, including all of the indigenous pottery of the Americas. All Ancient Greek and Ancient Roman pottery is earthenware as well. An everyday example of earthenware would be the terracotta pots used by gardeners.

Bamana potters preparing earthenware storage vessels for firing, Mali,

Stoneware represents a technological advancement over earthenware. It is fired at higher temperatures, between 1,100 °C (2,010 °F) and 1,300 °C (2,370 °F), usually in some kind of purpose-built kiln. For this reason, it is stronger than earthenware, and can hold water and other liquids. Like earthenware, stoneware clays are residual, but may have been processed to produce a finer, more homogenous material. Stoneware was first developed in China, and rose to become an art form there, as well as in Japan and Korea. Stoneware production came much later to Europe, not becoming widespread until the Renaissance. Most utilitarian pottery and studio pottery is made of stoneware (see below).

Stoneware Shigaraki tea jar, Shiga prefecture, Japan. 19th century.

Porcelain is distinct from earthenware and stoneware for two reasons. First, it is fired at higher temperatures, between 1,200 °C (2,190 °F) and 1,400 °C (2,550 °F). Second, it is made from extremely fine mineral clays (primarily kaolinite), which form in situ from the decomposition of other silicate minerals (primarily feldspar). At high temperatures, kaolin clay vitrifies, becoming a tough new material (even forming a new mineral, mullite). For this reason porcelain can be made into light, thin vessels that are extremely durable. Once again, this was a Chinese innovation, well underway by the Tang dynasty (AD 618–906); porcelain was not produced in Europe until the 17th century. Porcelain is the material used in fine china, as well as in a myriad of laboratory and industrial applications.

Porcelain moon jar (dalhangari), Joseon Dynasty (18th century), Korea

We should also mention fritware (sometimes referred to as stonepaste or faience), an unusual type of ceramic developed in the Middle East. It is a sort of regional work-around intended to achieve the appearance of porcelain, without the use of either kaolin clay or high-temperature kilns. In fritware, a large proportion of finely-ground silica "frit" is added to the clay, reducing its fusion temperature (an organic binder may be added as well). As a result, a glassy, porcelain-like ceramic can be produced at a much lower temperature. Some of the finest early Islamic pottery is fritware.

A 13th century. Iranian under-glazed fritware dish

Now, let's look at the terms we use to categorize pottery based on why it is made, and by whom. The ceramics offered on this site generally fall into one of four categories: folk pottery, utilitarian pottery, art pottery, and studio pottery (there is definitely some overlap between these categories). We hope to delve into each of them in more depth elsewhere in this blog.

Folk Pottery

We use this term for anonymous, hand-made ceramics created to serve practical needs. This term (literally, “people's pottery“) is often used in the antique trade to describe pottery from the American South, or Colonial-era redware from New England (both of which have roots in traditional European folk pottery). We use “folk pottery” for any traditional, hand-made pottery, from anywhere in the world. Like indigenous languages, many folk pottery traditions have become extinct, but others have prevailed against all odds. Strong folk pottery traditions persist in Japan, Morocco, Mexico, Turkey, Mali and other places. Some folk pottery traditions (e.g., Pueblo Indian pottery from the American Southwest) have outlived their practical origins, and have become more akin to studio pottery (see below). It should be noted that there are many commercial reproductions of "folk" pottery on the market.

A stoneware figural jug with a snake handle, breasts, and God-knows-what, Ohio, c. 1860

Utilitarian Pottery

We use this term for pottery created for primarily for industrial and commercial uses. Almost all utilitarian pottery is mass-produced stoneware, although some is hand-crafted, or at least hand-glazed (there is some overlap between folk pottery and utilitarian pottery, of course). Examples include butter churns, fermentation crocks, bottles for ink, beer, and wine; jars for pickles and preserves; and jugs for molasses, whiskey, et c. Utilitarian pottery had its heyday in the 19th and early 20th centuries, after the industrial revolution, but before the advent of plastics. Tile, clay pipe, and electrical insulators are a few forms of utilitarian pottery that have persisted into the present.

A collection of 19th century stoneware inkwells.

Production Pottery & Art Pottery

These terms refer to mass-produced ceramics made in workshops or factories, by workers under the supervision of a designer. Generally, this kind of pottery is slip-cast (made in molds), then finished and glazed by hand. “Art pottery” was a type of decorative production pottery manufactured for sale to the burgeoning middle classes in Britain and America in the late 19th and early 20th centuries. Some notable early art potteries include Doulton, Linthorpe, and Minton’s in Britain; Dedham, Roseville, and Rookwood in America. There were numerous art potteries in continental Europe as well, and even in Japan (such as the Tokanabe pottery sold through the Sears catalog).

Much Victorian (and later) art pottery is kitschy and repetitive, but the Art Nouveau and Arts and Crafts movements breathed new life into the form. Important potteries of this period include Fulper, Grueby, Marblehead, Teco, and Wheatley. From the early 1940s to the early 1960s (aka the mid-century period), there was another boom in American art pottery, led by the profusion of cheerful and ubiquitous "California Pottery." Major California potteries included Bauer, Metlox, Pacific Clay Products, and Vernon Kilns. In the 1960s and 70s, Stoneware Designs West, Pottery Craft and others began producing art pottery in the style of studio pottery (see below), which can create some confusion for the modern collector!

Double-Gourd Matte Green Buttress Vase from Teco Pottery c. 1910

Studio Pottery

The idea of the "studio potter" grew out of the Arts and Crafts movement in the early 20th century. The term was first used by Charles Fergus Binns (1857 – 1934) director of the New York State School of Clay-working and Ceramics. Binns and others were alarmed by the proliferation of homogenous, mass-produced "art pottery" (see above). Instead, they championed the value of traditional craft, and emphasized the importance of the individual potter’s genius. We reserve the term studio pottery for the work of professional potters who have studied their craft (perhaps apprenticing with master potter) and gained a notable level of skill. Hopefully, they will have studied formally, and devoted years to the art and science of ceramics. Many potters coming from folk pottery traditions have become studio potters of great renown (please see our longer post on this subject).

Vessel by California studio potter Paul Soldner, 1960s